Improvement in piano-forte stools



\ ititd tatet @sind dtljlw.

Letters Patent No. 94,387, dated August 31, 18.69.

IMPROVEMENT IN PIANO-PORTE STOLS.

The Schedule referred to in these Letters Patent and making part of the same.

To all whom 'it 'may concern:

Be it known that I, JOSHUA' BRIGGS, of Peterborough, in the county of Hillsborough, and State of New Hampshire, have invented an Improvement in Piano- Forte Stools; and I do hereby declare that the following, taken in connection with the drawings, which accompany and form part o f this specification, is a. description of my invention suicient to enable those skilled'iuthe' art to 'practise it.l

In that class of piano-forte stools, each having a. round seat, supported upon a screw-threaded spindle, which turns in the pillar of the stool, the necessity of a baclesupporting device is often felt, especially in the long hours of practice of learners. My invention is intended to obviate this diiculty, and I ei'ect this object by combining with the seat a removable back,l

.` the lower ends` of tivo vertical posts or bars of which ft into sockets, having 'long right-angular metal tonguepieces, which extend under the seat and into or through metal loop-plates screwed to the under surface of the seat. lIt is in a piauoforte stool having this provision that my invention consists.

The drawings represent the seat of. a round pianoforte stool embodying the improvement, the screwspindle and the supporting-base and pillar not being The foot of cach post disets and fits tightly into a metalesocket, f, from whichiprojects a right-angular tongue, g, as seen ,at A and B.

To the bottom of the seat are fixed two metal loops, h, into and fronrwhich the tongues g readily slide, the tongues tting snugly within the loops, so that when the back of the person sitting upon the stool is pressed up to the seat, the bach b will be so braced ,as to be relatively fixed and stationary. When thus in position, it forms asecnre support for the' back of the performer, and is not distinguishable from ,a permanent fixture, while, by slipping the tonguesffrom the loops, the stool is immediately lreconverted into a hackless stool, as perfect in =form 'as if it had no provision for application of the removable back-supporting device.

The back is exceedingly simple in its adaptive construction, adds but averysmall amount to the cost ot the stool, 'in uo waydetracts fi'om the appearance of the seat, and makes a lvery useful adjunct.

I do not claim, broadly, a chair having a removable back; but

I claim the removable socketpiecef; having a tongue, g, cast iutegraltherewith, substantially as and for the .purpose set forth.

f Also, the removable back, whose posts are fitted in metal sockets j; of tongues g, the latter being adapted to enter and be held by metal loops h, secured to the bottom of the' seat, as shown.

JOSHUA BRIGGS.

Witnesses J. B. ORosBY, FRANCIS GoULD. 

